N-Nitrosamine Mini-event -Dr. Teasdale (keynote speaker)


Date: 14 June 2022

Time: 13.00 (BST), 14.00 (CEST), 8.00 (EST) - 17.30 (BST)

This NEW free to attend webinar / Hopin mini-event seeks to present the very latest in terms of N Nitrosamines, tracking the evolution of the issue through the regulations as well as looking at specific risk factors and the scientific investigations currently being undertaken to both better understand and contextualize the range of potential risk factors. Trying, where possible, to tease out what is risk and what is not. In parallel, it simultaneously looked at the latest advances in technology to support both research and risk assessment.


Good idea, Andy, need to really understand if we are chasing flies with swat missiles?

1 Like

Many thanks for sharing. Looking forward to understand the limits derivation for new nitrosamines.


Outline Program:

1.00 Event Opens – Visit the Sponsors / Exhibitors

2.00 Plenary Session / Key Note Speaker – Dr Andrew Teasdale, Chair of AstraZeneca Impurities Advisory Group and Head of External Advocacy @AndyTeasdale

3.30 Hosted Discussion Session – Lhasa
How can nitrosamine risk assessments be supported by in silico systems and data sharing initiatives?

4.00 Hosted Discussion Session – Waters
Tools for Optimising Quantitative Performance and Eliminating Analytical Doubt in Trace Impurity LCMS Analysis

4.30 Hosted Discussion Session – ACD Labs
Using CMC Decision Support to Enhance Control Strategies

4.15 Visit the Sponsors / Exhibitors

5.30 End

In case you missed the presentation by (@AndyTeasdale) Dr. Teasdale, please find below the presentation deck that he kindly shared. As soon as we have more information on the recordings, I will share it here.

Facing-the-challenge-of-effective-control-of-N-NOs.pdf (6.2 MB)

1 Like

Recording here: Link

Thank you for sharing, @Naiffer_Host. I enjoyed this excellent webinar.

I’m interested in the purge calculation of NDMA in the Metformin synthesis. And I have no idea why a trace amount of NDMA includes in the crude mixture. Did water bring the nitrosating agent? Or does DMA Hydrochloride originally contain NDMA? Please teach me, @AndyTeasdale.

Anyway, NDMA from this cause does not look serious concern. It’s helpful to understand the practical purge of NDMA and DMA. It is fantastic!!

Hi Yosukemino,

Actually Mr. Teasdale answered this question in the Q&A session. It was well not 100% sure, but it seems DMA comes with traces of NDMA. Content of Nitrite in purified water/ process water is negligible and not enough to form the quantities of NDMA seen in Metformin AI.

In any case, maybe I am forgetting something. But I hope this helps you.

1 Like

Thank you for sharing helpful information, @Diego_HM. I missed the Q&A session. And DMA hydrochloride seems to include NDMA at the level of control limit, according to the upper slide on my post. It’s interesting!!

And we should be careful to use DMA hydrochloride.

Adding @schlinjo1975 to the discussion, because this study is based on the work he lead. I found extremely insightful the side-by-side comparison of the experimental work with the purging calculations. I am really hoping this parallel study is published with the same level of details that Joerg et al put in the original publication.

Here is the post about that article just for reference:

1 Like

“NDMA in the system may not be formed from DMA during the synthesis process but rather introduced by the starting material DMA HCl and gradually enriched in the recycled solvents” From 3.1 Results and discussion / Depletion of NDMA introduced during API manufacturing by double crystallization


Thanks a lot, @Naiffer_Host. I have been searching for this paper.

DMA hydrochloride seems initially to include NDMA and is contaminated further due to recycled solvents. It’s reasonable.

I guess nitrogen oxides in the air may react with DMA hydrochloride.